You can click them to view the full-size images.
Desktop on absolute64-current (12/11/2021), with both file managers -- qtFM on the top left, and arox (rox-filer derivative) on the right. qtFM is new, and along with udisks (no gvfs) is also controls disk mounting. The default view is in detail mode. qtFM is a good lightweight file manager for popping around the system.
Arox is open in large icon mode. And as you can see -- it works as a good thumbnail viewer for many types of images, and includes thumbs with transparency. The "+/-" eyeglass icon controls the thumbnail size. (See red arrow) Left-click to make large or largest, right-click to make smaller or smallest. Extremely efficient as a viewer. You can also drag and drop file links directly from a browser into a filer window. (arox uses wget2 to impliment this.)
As you can likely start to see, Absolute is set up with a priority to view and edit images.
A few different viewers/editors are used on Absolute -- but the most-used viewer is the legendary FEH. Fast and stable, written in C, and stripped-down and specialized for use in Absolute. "Switch to GIMP" closes FEH, and opens the image in GIMP for editing.
Why two file managers?
Because I use two :-)
Arox is the viewer/downloader. qtFM for disk mounting and tooling around fast. And if I break one because I like to screw around with the code... I have a fallback. CLI is just TOO SLOW when I want to get things done. Image editing, programming and computer repair -- that's what I do. I base the distro on Slackware because it is stable and sparse. On top of that I like to use the best software. Audacity, LibreOffice, GIMP, FEH, Audacious, Filezilla, Scite, Calibre, Inkscape, Firefox, Shotcut, Gparted, MPV -- all apps I consider to be the best at what they do.
This gathering of software leads to quite a few toolkits and libraries, and sometimes several apps that can be brought to bear on a particular file. Not the UNIX philosophy, by any means. But I want all the best software, working together, without the operating system getting in my face. That's the Absolute Way !